What is the difference between microemulsion and nanoemulsion?
The fundamental component formation of a nanoemulsion is very similar to those found in a microemulsion as mentioned above. The only distinctive difference that separates a nanoemulsion from a microemulsion is their thermodynamic stability, i.e., a microemulsion is thermodynamically stable while a nanoemulsion is not.
What is difference between surfactant and cosurfactant?
Pure surfactants often organize well at a liquid/liquid boundary, which leads to relatively stiff interfaces or even liquid-crystal phases. To achieve ultralow interfacial tension for enhanced oil recovery applications, a cosurfactant is added to disturb this organization at the liquid/liquid interface.
What are the four compositions of microemulsion?
4 Microemulsions. Microemulsions are clear, thermodynamically stable, isotropic liquid mixtures of oil, water, surfactant, and cosurfactant.
What is a Cosurfactant?
Cosurfactants are the agents used to increase the solubility of drugs in SLNs/NLCs by reducing the interfacial tension to a limit below that of the surfactants.
What is microemulsion method?
The microemulsion technique promises to be one of the versatile preparation method which enables to control the particle properties such as mechanisms of particle size control, geometry, morphology, homogeneity and surface area.
What is microemulsion Slideshare?
Microemulsion is an isotropic mixture of oil, surfactant, Cosurfactant and drug. Upon mild agitation followed by dilution in aqueous media, such as gastrointestinal (GI) fluids, the systems can form fine oil in water (O/W) Microemulsions which usually have a droplet size less than 100 nm.
What is surfactant and cosurfactant?
A chemical added to a process to enhance the effectiveness of a surfactant. In the oil industry, cosurfactants are often used to increase the oil-solubilizing capacity of microemulsion surfactant systems. An example of such a cosurfactant is a long-chain alcohol.
Why co-surfactant is needed in forming the microemulsion?
The roles of a co-surfactant are to increase the fluidity of the interface, destroy liquid crystalline or gel structure which would prevent the formation of the microemulsion and adjust the HLB value and spontaneous curvature of the interface by changing surfactant partitioning characteristic [4].
What is emulsion and microemulsion?
Emulsions and microemulsions are both stable dispersions of oil-in-water or water-in-oil. Emulsions are stable dispersions of immiscible liquids, but they are not thermodynamically stable. We say that they are kinetically stable. These type of dispersions are sometimes called macroemulsions.
What is microemulsion polymerization process?
Definition. Microemulsion polymerization is defined as polymerization involving a radical chain propagation reaction with vinyl monomers in one phase of a microemulsion, and the produced polymer colloid is denoted as latex.
What is microemulsion example?
There are three kinds of microemulsions: oil dispersed in water (o/w), water dispersed in oil (w/o), and bicontinuous. The presence of o/w droplets is likely to be a characteristic of microemulsions where the amount of oil is low.
What is microemulsion used for?
Microemulsions have many commercially important uses: Water-in-oil microemulsions for some dry cleaning processes. Floor polishers and cleaners. Personal care products.
How are surfactant and cosurfactants used in nanoemulsions?
Surfactant and cosurfactant are preferentially adsorbed at interfaces, thus reducing the interfacial energy and providing a mechanical barrier to coalescence, and improving the thermodynamic stability of the nanoemulsion formulations [13]. Common cosurfactants include ethanol, propylene glycol, and poly (ethylene glycol) (PEG).
How does cosurfactant affect the microemulsion electrolyte?
The viscosity of the microemulsion electrolyte is increased when the concentration of viscous alcohol is increased, causing a reduction in the EOF velocity. The droplet also increases in size as it incorporates more co-surfactant, reducing both its charge density and its electrophoretic mobility.
How are cosurfactants used in the formulation of sneddss?
Cosurfactants in SNEDDSs are used to cooperate with surfactants to increase the solubility of drugs and enhance the dispersibility of hydrophilic surfactants in the oil phase, thus promoting formulation homogeneity and stability [18].
How does a cosurfactant help to stabilize a system?
Cosurfactants of ionic or nonionic nature help in the stabilization of a system by formation of dynamic micelles and further reducing the interfacial tension.